This invention relates to a hook plow mining apparatus. More specifically, this invention relates to a hook plow mining machine especially adapted for use in conjunction with the fixed arch shield mining technology described in application Ser. No. 509,489. This technique is particularly useful in the mining of oil sands, but is also capable of use for coal mining, mining of oil shale, and mining other minerals capable of being mined by longwall techniques. The mined material, after being cut from the mining face, falls onto a longitudinal conveyor operating within the mining shield, and is then conveyed from the mining face to suitable collecting means operating at the ends of the face for ultimate conveyance through a shaft to the ground surface.
The mining shield comprises a plurality of individual arch sections in side-by-side abutting relationship, each arch section being advanceable towards the mining wall as the mining wall recedes, thereby creating a void posteriorly of the mining shield, leaving the back unsupported and free to gradually collapse behind the shield. The cutting equipment is normally not manned, the equipment travelling between a pair of operators stationed at the ends of the movable shield.
This technique combines the best features of longwall mining as used for mining coal, and block caving as used for mining metal ores. Further, some of the undesirable features of these prior art techniques have been eliminated. One such feature is the high cost of maintaining hydraulic roof support systems. Another problem with longwall coal mining which has been alleviated by the fixed arch shield technique is the necessity of using long, heavy chains stretched the full length of the longwall face for the transmission of power to propel the mining machines along the mine face. The amount of power which can be transmitted by such chains is of course dependent upon the strength of the weakest link in the chain, and is also decreased by wear. The power transmission system preferably used in the fixed arch shield technique is disclosed in application Ser. No. 549,823.
Although the fixed arch shield technique may use such mining machines as armored face conveyors, shearers, and plows, various degrees of modification are necessary so as to adapt these machines to operate within the shield. The present invention relates to plows for use in conjunction with this type of shield.
The modifications which are necessary include retractability of the plows so that the apparatus may be transported within the shield when not engaged in actual plowing, as well as expansibility so that the plow, when advanced forward out of the fixed arch shield so as to engage the mining face, can expand vertically and plow the mining face to the full height of the normal cut of the fixed arch shield.